WHAT ARE THE EFFECTS OF WALL THICKNESS OF PLASTIC PRODUCTS ON QUALITY

The wall thickness of the plastic parts processed by injection moulding has a great influence on the quality. When the wall thickness is too small and the flow resistance is too large, it is difficult for large and complex plastic parts to fill the cavity. The minimum size of the wall thickness processed by plastic parts should meet the following requirements:

It has enough strength and stiffness.

It can withstand the shock and vibration of demoulding mechanism when demoulding.

Can withstand the fastening force when assembling.

The minimum wall thickness stipulated by the injection processing plant varies with the variety, brand and size of the plastic parts. Excessive wall thickness in the processing of plastic parts not only wastes raw materials, but also increases the time of moulding and tends to cause incomplete curing. For thermoplastic, it increases the cooling time. In addition, it also affects the quality of the processing of plastic parts. The thickness of the same injection part should be as uniform as possible. Otherwise, additional stress will be generated due to uneven cooling and curing speed.

It is very important to determine the wall thickness of plastic products. The wall thickness of plastic parts depends on the requirements of the use of plastic parts first: including the strength, quality cost, electrical performance, dimensional stability and assembly of the parts. Generally, the wall thickness has empirical values, which can be determined by referring to similar values (e.g. the wall thickness of iron is 2 mm, and the vacuum cleaner is 2.5 mm). The points of attention are as follows:

The wall thickness of plastic parts should be uniform as far as possible in injection processing, so as to avoid being too thin, too thick and sudden change of wall thickness. If the wall thickness of plastic parts must be changed, gradual change or arc transition should be adopted. Otherwise, the plastic parts will be deformed, the strength of plastic parts will be affected, and the fluidity of plastic parts will be affected due to uneven shrinkage.

The wall thickness of plastic parts is generally in the range of 1-5 mm. The commonly used value is 2-3 mm.

Minimum wall thickness of common plastic parts and recommended value of common wall thickness: (mm)

Try not to design the stiffeners and screw columns too thick. Generally, it is recommended to take half of the thickness of the body wall to be safe. Otherwise, it is easy to cause appearance problems such as miniature.

Try not to design the parts into separate flat plates. The size is very small. Otherwise, the deformation will lead to uneven parts.